the shadow you are seeing is the return wire enclosed in ceramic to protect it. cheap kits will usually have the wire at the 12 o'clock position so when the projector throws the light on the floor you will see the return wire. OEM kits and higher end hid kits like mcculloh will have the return wire at the 6 o'clock position and you do not see it on the road. some have cut the tab on the h7 bulb and rotated the bulb to where you do not see the shadow. halogen reflectors dont need to worry about this but they create tons of glare versus halogen projectors. the best thing to do is retrofit HID projectors from honda s2000 or acura tsx.

http://faqlight.carpassion.info/hid-...up-down-h7.jpg
http://www.team-integra.net/sections/articles/showArticle.asp?ArticleID=973
http://faqlight.carpassion.info/hl-hid-bulbs.htm

"There is also something known as a return-wire shadow. The small ceramic insulator that runs the length of the glass will actually cause a dark spot if the capsule is viewed head-on. A car with factory HID will have headlamps that hide this shadow; halogen headlamps will have a dead spot where this wire sits, usually at the bottom."